For you mortar men out there?

[markshot]

Okay, last night I had some experimentation (CMBN 4.03) with 60mm in direct fire mode vs previous experience in indirect observer fire mode.

It seemed to me that direct they got on target pretty fast compared to the occasional comedy of indirect where by the time they zero the target, they are out of ammo.

This got me thinking ... with indirect fire there are 3 points:  TARGET, FO, GUN.  Does it improve zeroing to align these points in a straight line or relatively straight line.  I mean in real life, it seems aiming in a single dimension is an easier problem than two dimensions.

Thoughts and/or experience (virtual or real)?

Thanks.

[chuckdyke]

In real life there is direct communication between members of the platoon and the mortar men. In the game make sure that the intel of the security squad is shared asap. The security squad is the squad which moves to find contact with the enemy. My method is 2 scouts split from the 1st squad followed by the HQ and the mortar-team the 1st squad provide fall back and secure an area which conceals the mortar team but enables the mortar to engage the area to 300-500mtrs. Ideally the HQ will get contact icons which is shared with the mortar team and is ready to engage the area of the contact icons. The other 2 squads will have shared the intel and will seize terrain and eliminate the enemy. The 60mm is the key to success with US forces. 

[Combatintman]

Linear deployment of mortar and observer to line up with a target is something I have never heard of.  So, while I am not expertly versed in mortar procedures, I suspect it is something that doesn't happen or is taught as the 'ideal' solution.  With all observed fire, so long as the observer can read a map accurately, see the target and can then communicate that to Fire Direction Center/mortar line you are well on the way to getting rounds where you want them.  So long as the people at the FDC/mortar line transcribe those grids accurately and they are passed on to the individual mortars accurately you are further down that path.  If the mortars/guns are correctly sited and even better, surveyed, and the crews know how many turns of the dial = 'up 100 - left 50 etc' on the aiming mechanism and how many charges are needed for the required range, then they should hit the target.  Gunnery is lots of sums and works best if you know where the target is, what the weather's like and where your guns/mortars are so does not need mortar, observer and target to be in a nice straight line.

Edited June 15, 2021 by Combatintman

[chuckdyke]

He is discussing the 60mm in the direct fire mode on platoon level. Communication is verbal between members of the same platoon. In this fashion the mortar team has not an LOS but can plot an LOF on a contact icon which is or was shared through his C2. The tactic I used in FB. In the game if you want to plot a linear mission you have the ridiculous situation in which the HQ who is maybe 25 mtrs away from the mortar must use his radio to achieve this. @Combatintman what you mean by Linear Deployment?

Edited June 15, 2021 by chuckdyke

[Combatintman]

10 minutes ago, chuckdyke said:

He is discussing the 60mm in the direct fire mode on platoon level. Communication is verbal between members of the same platoon. In this fashion the mortar team has not an LOS but can plot an LOF on a contact icon which is or was shared through his C2. The tactic I used in FB.

Then why did he mention an FO (forward observer) and indirect fire in his question smarty pants?

[chuckdyke]

1 minute ago, Combatintman said:

Then why did he mention an FO (forward observer) and indirect fire in his question smarty pants?

The HQ or any other member of the platoon can observe an enemy unit they want to target. In the game it is possible for the mortar who has only a contact icon to be just out of LOS of the enemy but still can take them out by plotting a direct LOF. I found this tactic works in FB to take MG42s. 

[domfluff]

Original point is an interesting one, and is worth pondering.

TC 3-22.90 goes into some detail - the chapter "Fire without a Fire Direction Center" is the appropriate one, because this is best represented by non-TRP fire missions in game. (We should have far more TRPs than we typically get in CM scenarios, but that's a whole different argument).

Quote

(1) The tactical employment of the mortar usually requires the FO to be in a position other than at the mortar. However, if the FO is located within 100 meters of the mortar position, the deviation error he reads in his binoculars can be applied directly to the sight FM 23-90/TO 11W2-5-13-21 8-2 without computation. This is true because the angle between the observer-burst line and OT line is equal to the angle between the mortar-burst line and GT line. Any slight difference between these two angles is compensated for by the inherent dispersion of the weapon and the bursting area of the round

But the maths for adjusting for the situations where this is not the case is pretty simple:

 

O-T = Observer -> Target line, G-T = Gun -> Target line.

The point that this stresses, however, is that where the FO can't be within 100m of the mortars, they should be within 100m of the G-T ine. Partly I suspect this is because it's going to make the maths easier, but whether there is increased accuracy from this in CM is worth testing. I know I've rarely given much thought to my relative positioning of FO and artillery before now. Staying within 100m of the mortars should decrease call-in time, if nothing else.
 

Edited June 15, 2021 by domfluff

[Ultradave]

1 hour ago, chuckdyke said:

He is discussing the 60mm in the direct fire mode on platoon level.

No, he's not. He specifically stated indirect fire with "target, FO, gun."

Lining up with the observer on the line of fire is much easier if you have no FDC. This is because without a FDC there isn't a way to plot the observer's line of observation and convert HIS right 200, drop 200, into what that means in left/right add/drop for the mortars to calculate new deflection and elevation numbers to fire. So if he is close to the line of fire (no matter the distance from him to target or mortar), his add drop left right will be the same as what the mortar needs to account for. Then "all" they need to do is convert range to firing data. The FO just needs to have a good estimate of the distance at the target location. 

Normally in indirect fire, WITH a FDC, it makes no difference at all where the FO is in relation to the target or firing element. In the Call for Fire (CFF) the FO will report HIS azimuth to the target. That's the compass direction from the FO to target. In the FDC you plot a back azimuth from the target. Somewhere along that line is the FO. Now when the FO provides corrections, you plot them in relation to that FO to target azimuth in meters L/R U/D (what the FO is seeing and wants). Mark the new target point. Then switch to the firing line and calculate new deflection and elevation to that new adjusted point. The FO can be anywhere. As long as HE (the FO) knows where he is, and can estimate reasonably accurately the range from him to the target and provide accurate L/R U/D corrections (which is why he needs to have a good range estimate from him to target), then the FDC can quickly convert his corrections into gun corrections.. 

Using a 60mm in direct fire, it's like having the observer right on the line of fire. Observe the rounds, estimate corrections, covert the distance in meters corrections to deflection and elevation corrections. Whump. Do it again.

Dave

[chuckdyke]

6 minutes ago, Ultradave said:

No, he's not. He specifically stated indirect fire with "target, FO, gun."

You don't know the discussion we had last week. It is direct fire to a target spotted by the platoon, the mortar itself has no LOS. I suggested this instead of wasting ammunition on spotting rounds. This is indirect fire by definition. Indirect fire is aiming and firing a projectile without relying on a direct line of sight between the gun and its target. 

 

[Ultradave]

5 hours ago, markshot said:

This got me thinking ... with indirect fire there are 3 points:  TARGET, FO, GUN.  Does it improve zeroing to align these points in a straight line or relatively straight line.  I mean in real life, it seems aiming in a single dimension is an easier problem than two dimensions.

Here's his question. Whatever you discussed last week, RIGHT NOW he's asking about indirect fire and the FO's relative bearing to the target. The question is quite clear and so is my answer.

Dave

Edited June 15, 2021 by Ultradave

[chuckdyke]

3 minutes ago, Ultradave said:

The question is quite clear and so is my answer.

still subjective better ask him yourself. He says what option to use a single dimension or two dimensions. The FO with a 60 mm on platoon level is its HQ or any other member. Communications can be given verbally or by signals. The game allowed for this, technically it is a direct fire mission inside the game. I agree with you if there is a need for radio and reference maps. On platoon level I illustrated indirect fire which the game allows. The HQ is the FO a squad received incoming fire the mortar with no LOS got the contact icon and the game let me plot a LOF to the target. This can happen in real life too. The game mirrored this realistically by letting the first two rounds fall shy of the target before it was effective.  

[Ultradave]

Whatever. He asked for experience virtual or real. I gave him real world. And I'm quite well aware of the definition of indirect fire, thank you.

I'm done here. 

Dave

[Combatintman]

1 hour ago, Ultradave said:

Whatever. He asked for experience virtual or real. I gave him real world. And I'm quite well aware of the definition of indirect fire, thank you.

I'm done here. 

Dave

Have a like - me too, at least the OP has an answer to the question he actually asked.

[markshot]

I am sorry if offended anyone with the question.

I really don't know how mortar aiming is handled when an HQ spots for an organic mortar (by this I mean indirect that I use the fire mission tab from the HQ, and not the target from the mortar team).

I am just trying to learn to play the game better.

Thank you, all.

[Ultradave]

3 minutes ago, markshot said:

I am sorry if offended anyone with the question.

I really don't know how mortar aiming is handled when an HQ spots for an organic mortar (by this I mean indirect that I use the fire mission tab from the HQ, and not the target from the mortar team).

I am just trying to learn to play the game better.

Thank you, all.

Ah, good. That's the question I answered with the discussion about azimuth to the observer and converting from the FO point of view to the firing element point of view.

Dave

[LukeFF]

40 minutes ago, markshot said:

I am sorry if offended anyone with the question.

I really don't know how mortar aiming is handled when an HQ spots for an organic mortar (by this I mean indirect that I use the fire mission tab from the HQ, and not the target from the mortar team).

I am just trying to learn to play the game better.

Thank you, all.

You didn't offend anyone or do anything wrong - it was a good question. There's just another participant in this discussion that doesn't like being corrected. 

[Combatintman]

@markshot - no issues with the question from me either @LukeFFhas pretty much summed the situation up.

[domfluff]

Have done some quick, non-definitive tests, but I can't see a difference in-game, sadly. Clearly having the FO close to the mortar will improve the C2 connection - this would be especially important in a high EW environment, but the call in times all seem to be about the same, no matter what the orientation of FO, target and mortar.

[Ultradave]

Call in times for the initial mission delay? That would make sense. The initial call for fire includes the FO azimuth to target but that info is not used until the FO provides corrections on the adjusting rounds. 

 

[domfluff]

Sorry, I meant the time between the initial spotting rounds to calling Fire for Effect. Again, brief, non-definitive tests, but so far there hasn't been an obvious difference.

[Ultradave]

I see. It doesn't take a lot of time to do the calcs to switch from the observer's iine to the firing line. And for mortars, time of flight is quite significant when compared to howitzers (factor of 2x - 3x depending on range), so that calculation is even less of the total time. So while it might be marginally easier to have an observer on the line of fire as opposed to a significant angle, that's going to be a VERY small difference in the total fire mission time.

So for indirect fire I would not expect to see much difference in on line of fire or off line of fire FO location. Perhaps I wasn't clear enough with that by getting too much into the details of the data calcs.

For direct fire, it should be quite a bit faster because the mortar crew is observing and rather than plotting anything, they will quickly convert a "drop 100" adjustment, for example, to a quick adjustment of the elevation of the piece and fire again. 

If you are using some kind of hybrid where it's sort of direct fire because you have someone a distance away yelling corrections or giving hand signal corrections (never heard of doing this btw), without firing charts, then being off line makes a difference, and the mortar crew would have to do some trig to convert. (much easier to have a plotting board than try to draw and solve the triangles). So in THAT sort of hybrid case, it should make a difference. This hybrid is what chuckdyke keeps describing. They are different things. 

But you specifically asked about an indirect call for fire using the fire support tab, which implies a FDC of some kind with therefore charts and darts with firing sticks/tables.

I hope that's helpful. Incidentally, these basic indirect fire principles apply to howitzers as well. Of course, for direct fire of a howitzer it's a different thing entirely than with a mortar.

Dave

Edited June 15, 2021 by Ultradave

[chuckdyke]

OK with a Platoon HQ standing 32 meters (4 action squares) next to his mortar he needs to go through his radio for a fire mission while the problem can be solved by plotting a direct fire with the mortar team under cover, It makes a lot of sense especially when he has only 20 rounds. @LukeFF    feel free to call me by my name. Your trolling at my posts is of no value whatsoever. In my game the mortar received the contact icon from the HQ and could fire over the crest to engage an enemy unit he couldn't see himself. Fortunately, the designers allowed for instances like these. I suggest you purchase a dictionary and look up the definition of indirect fire. Right or wrong is not determined by a popular vote. 

[Badger73]

19 hours ago, markshot said:

<snipped>

Does it improve zeroing to align these points in a straight line or relatively straight line.  I mean in real life, it seems aiming in a single dimension is an easier problem than two dimensions.

Thoughts and/or experience (virtual or real)?

Thanks.

During WW2 (the time period of your question) at the line company/platoon level, aligning the FO along the same directional line as the guns was the preferred option.

The techniques WW2 Forward Observers used to adjust fires, Fire Direction Centers used for re-calculations, and crew drill traversing the guns were not as good as those used today (even without computerized FDC's).  I don't know how the WW2 CM games might handle it as opposed to those historical experiences.

Edited June 16, 2021 by Badger73

[chuckdyke]

4 minutes ago, Badger73 said:

I don't know how the WW2 CM games might handle it as opposed to those historical experiences.

By common sense. They may have called to the mortar crew something like "50 yards over". By passing the fire direction center. According to the BF Dictionary it becomes then a direct fire mission. I think it sound silly calling by radio the fire direction center for a mission when the HQ is in direct contact with his mortar and crew. I solve the problem nine times out of ten by direct fire according to the BF definition which I see as indirect fire. 

[chuckdyke]

The difference between direct and indirect fire. According to BF. Same position same observer same result. Indirect fire will go through the fire control center.

 

 

Edited June 16, 2021 by chuckdyke
2nd picture